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arXiv · 2008.01225

An Inconsistent Forcing Axiom at $\omega_2$

Stevo Todorčević·Shihao Xiong
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Abstract

We show that the forcing axiom for countably compact, $\omega_2$-Knaster, well-met posets is inconsistent. This is supplemental to an inconsistency result of Shelah and sets a new limit to the generalization of Martin's Axiom to the stage of $\omega_2$.

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Stevo Todorčević, Shihao Xiong. 2020-08-03. An Inconsistent Forcing Axiom at $\omega_2$. https://arxiv.org/abs/2008.01225

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